1. Technical Field
Embodiments of the present invention relate to a method according to the introductory portion of the attached claim 1.
Embodiments of the invention also relate to a device according to the introductory portion of the attached claim 18.
Embodiments of the present invention further relate to a firearm according to claim 35.
2. Prior Art
Technique of the above referenced kind is previously known.
The accuracy of fire in rifle shooting and in handgun shooting is limited inter alia of the quality of the weapon and ammunition and of the kind of the sights used. One reason for the point of impact to vary from shot to shot may eg be that the bullet weight and gun-powder load varies from cartridge to cartridge. Even if the weapon is fired in the same direction and under the same further conditions during a series of shots, the point of impact of the shots will get a certain spread which is caused by the quality of the materials used. For modern weapons, however, the spread caused by shortcomings of the weapon precision or the quality of the ammunition by free hand shooting, i.e. without any external support for the weapon, is small compared to the spread caused by the marksman himself by not being able to hold the weapon still enough during the aiming and for this reason will have it difficult to make a firing in the direction desired. In order to hit as good as possible the marksman must try to hold the weapon still in the direction towards the target and make the firing at a moment when the aiming direction, during the unavoidable and partly random movement around the target, coincides with the direction towards the target. The better the marksman can control the movement of the aiming direction up to a desired position for firing and the slower this movement is, the easier it is to make a good firing and get a good hit. What, inter alia, characterizes the unintentional barrel movements during the aiming is that these movements are comparatively fast and relatively small compared to the intentional changes of the aiming direction, which are bigger and slower.
In U.S. Pat. No. 5,834,677 a rifle with a built in servo system stabilizing the aiming direction and thereby improving the accuracy of fire is described. The barrel (the fire tube) is in this case suspended inside an outer pipe in which the barrel can move. The pipe around the barrel increases the total weight and moves the point of gravity forward which is a drawback since more power is then needed to hold the rifle horizontally. Further, the motors which shall affect the direction of the barrel are mounted in the forward end of the barrel which still further moves the point of gravity forward. The point of gravity in a conventional rifle is normally located to a point about right between the two positions where the right and the left hand, respectively, holds the rifle, i.e. about at the trigger. According to the present invention no external mechanic s around the barrel is needed to control its direction. Therefore the weight in front of the rifle point of gravity does not increase for this reason. Thus, the present invention may be applied to weapons with a relatively long barrel without impairing the so called balance, or, in other words, that the point of gravity is moved forward. According to the present invention a major part of the elements comprised by the servo system, i.e. motors, electronics and mechanics, are located at the weapon rear end, so that the weapon point of gravity is not moved forward by the additional elements.
A drawback with the design according to the U.S. Pat. No. 5,834,677 is that the sight, to be able to show the actual direction of shot, must be mounted on the barrel surrounded by the pipe. This complicates the design. The mounting of the sight according to the present patent is done in the same way as on conventional weapons. Therefore, according to the present invention the design becomes less complicated.
In U.S. Pat. No. 5,974,940 a system is described in which the direction of the barrel is stabilized by means of two linear motors. The weight and the positioning of these motors move the point of gravity forward and makes the weapon heavy in the front. In the same U.S. Pat. No. 5,974,940, the stabilizing servo system is activated by the trigger having to be pulled to a first position which activates the servo system. Firing is then done by the trigger being pulled further. The method may imply a risk that the marksman by mistake fires a shot instead of activating the servo system. Another drawback with this method of activating the servo system is that it reasonably needs considerable training to be applicable in an efficient and safe way. Normally, the trigger is not used for anything else but firing a shot. According to the present invention no change of the function of the trigger is needed since the activation of the servo system is done by the marksman when aiming presses a press plate against the shoulder and thereby closes a circuit which activates the servo system. The marksman does therefore not perform any special operation to start the servo system in addition to the ones performed at normal shooting.
An object of the present invention is, inter alia, to solve the problems associated with the prior art technique.